Fruits Of Milk Thistle Research Articles

Silymarin attenuates airway inflammation induced by cigarette smoke in mice.

Cigarette smoke (CS), which increases inflammation and oxidative stress, is a major risk factor for the development of COPD. In this study, we investigated the effects of silymarin, a polyphenolic flavonoid isolated from the seeds and fruits of milk thistle, on CS-induced airway inflammation and oxidative stress in mice and the possible mechanisms. BALB/c mice were exposed to CS for 2 h twice daily, 6 days per week for 4 weeks. Silymarin (25, 50 mg/kg·day) was administered intraperitoneally 1 h before CS exposure. Bronchoalveolar lavage fluid (BALF) was acquired for cell counting and the detection of pro-inflammatory cytokine levels. Lung tissue was collected for histological examination, myeloperoxidase (MPO) activity assay, superoxide dismutase (SOD) activities, and malondialdehyde (MDA) levels. The phosphorylation of ERK and p38 was evaluated by Western blotting. Pretreatment with silymarin significantly attenuated CS-induced thickening of the airway epithelium, peribronchial inflammatory cell infiltration, and lumen obstruction. The numbers of total cells, macrophages, and neutrophils, along with the MPO activity (a marker of neutrophil accumulation) in BALF, were remarkably decreased by silymarin in CS-exposed mice (all p<0.05). In addition, silymarin pretreatment dampened the secretion of TNF-α, IL-1β, and IL-8 in BALF. High-dose silymarin (50 mg/kg·day) administration also prevented CS-induced elevation in MDA levels and decrease in SOD activities (p<0.05). Furthermore, the CS-induced phosphorylation of ERK and p38 was also attenuated by silymarin (p<0.05). These results suggest that silymarin attenuated inflammation and oxidative stress induced by cigarette smoke. The anti-inflammatory effect might partly act through the mitogen-activated protein kinases (MAPK) pathway.

Simplified procedure of silymarin extraction from Silybum marianum L. Gaertner.

Silymarin, a mixture of flavonolignans exhibiting many pharmacological activities, is obtained from the fruits of milk thistle (Silybum marianum L. Gaertner). Due to the high lipid content in thistle fruits, the European Pharmacopoeia recommends a two-step process of its extraction. First, the fruits are defatted for 6 h, using n-hexane; second, silymarin is extracted with methanol for 5 more hours. The presented data show that this extremely long traditional Soxhlet extraction process can be shortened to a few minutes using pressurized liquid extraction (PLE). PLE also allows to eliminate the defatting stage required in the traditional procedure, thus simplifying the silymarin extraction procedure and preventing silymarin loss caused by defatting. The PLE recoveries obtained under the optimized extraction conditions are clearly better than the ones obtained by the Pharmacopoeia-recommended Soxhlet extraction procedure. The PLE yields of silychristin, silydianin, silybin A, silybin B, isosilybin A and isosilybin B in acetone are 3.3, 6.9, 3.3, 5.1, 2.6 and 1.5 mg/g of the non-defatted fruits, respectively. The 5-h Soxhlet extraction with methanol on defatted fruits gives only ∼72% of the silymarin amount obtained in 10 min PLE at 125°C.

Flavonolignans from Aspergillus iizukae, a Fungal Endophyte of Milk Thistle (Silybum marianum)

Silybin A (1), silybin B (2), and isosilybin A (3), three of the seven flavonolignans that constitute silymarin, an extract of the fruits of milk thistle (Silybum marianum), were detected for the first time from a fungal endophyte, Aspergillus iizukae, isolated from the surface-sterilized leaves of S. marianum. The flavonolignans were identified using a UPLC-PDA-HRMS-MS/MS method by matching retention times, HRMS, and MS/MS data with authentic reference compounds. Attenuation of flavonolignan production was observed following successive subculturing of the original flavonolignan-producing culture, as is often the case with endophytes that produce plant-based secondary metabolites. However, production of 1 and 2 resumed when attenuated spores were harvested from cultures grown on a medium to which autoclaved leaves of S. marianum were added. The cycle of attenuation followed by resumed biosynthesis of these flavonolignans was replicated in triplicate.

Effect of fertilization on the content of macronutrients in fruits of milk thistle (Silybum marianum L. Gaertn.)

Milk thistle was grown on a substrate with the texture of light soil, slightly acid in reaction and moderately abundant in available phosphorus, potassium and nitrogen. The effect of incremental nitrogen fertilization (0.0, 1.0, 2.0, 3.0 g N per pot) against the background of constant PK fertilization (P – 1.0, K – 1.5 g per pot) on the content of macronutrients in fruits of two forms of milk thistle, a cultivar called Silma and a population line bred in Poland, was tested in the first trial; the influence of boron fertilization was assessed in the second series and the impact of forms of magnesium fertilizers (MgCl 2 and MgSO4) was analyzed in the third variant of the experiment. The variety-specific traits had a significant effect on the content of nitrogen, phosphorus and potassium, but did not affect the concentrations of calcium, magnesium and sodium. The content of nitrogen in achenes of the population plant was 26.38 g N kg–1 d.m., compared to 25.16 g N kg–1 d.m. determined for cv. Silma. Fruits of the population line also contained significantly more phosphorus and potassium (by app. 17%), whereas the levels of sodium, calcium and magnesium did not differ in a statistically significant way between the two types of the plant. The highest nitrogen (27.62 g kg–1 d.m.) and phosphorus (8.78 g kg–1 d.m.) concentrations were obtained by applying 2 g N per pot. Sulphur introduced to soil in the form of magnesium sulphate raised the content of nitrogen in achenes of both forms of milk thistle.

A novel approach for the efficient extraction of silybin from milk thistle fruits.

Background:Milk Thistle fruit is an important herb popularly consumed worldwide for a very long time. Silybin is the main bioactive constituent of the herb, and it has been approved by US Food and Drug Administration (FDA) as a medicine to treat liver diseases. Presently, using conventional technology, the meal of Milk Thistle fruit is used as the raw material to extract silybin.Objective:To investigate the necessity of detaching husk from kernel of the herb and also to propose a novel approach to enhance the extraction technology in pharmaceutical practices.Materials and Methods:The husk of Milk Thistle fruit was detached from the kernel of the herb using an automatic huller specially designed for this application. The husk and the meal of Milk Thistle fruit was subsequently refluxed, separately, with production rate of silybin as index for comparison of their extraction effect.Results:The highest production rate was achieved under optimized condition. The husk was extracted 2 times (3 hrs each) using ethyl acetate, and the ratio of solvent to raw material was 8:1. The extract was allowed to be crystallized out.Conclusion:The separation of kernel from the husk of Milk Thistle fruit and using only the husk as raw material can largely enhance the extraction of silybin.

A multicentre open clinical trial to assess the tolerability and efficacy of Boldocynara®, a traditional herbal preparation for functional digestive disorders

Functional digestive disorders lead the list of visits to gastroenterologists and affect up to 40% of the population, with only a minority seeking medical care for it. Boldocynara®, a proprietary combination product consisting of artichoke leaves, milk thistle fruits, dandelion herb and root, and boldo leaves, has been traditionally used to treat indigestion. In this study including 75 patients aged 18 to 71 years and suffering from functional digestive disorders at least twice weekly since at least 2 months, Boldocynara® applied in a newly developed solid form at a dosage of 2 × 1 tablet daily proved to be well tolerated and efficacious in reducing these complaints as evaluated via the SF-LDQ measuring frequency and severity of dyspepsia, heartburn, regurgitation and nausea and a Global questionnaire on fat intolerance, upper abdominal pain, epigastric discomfort, abdominal bloating, postprandial fullness, flatulence, abdominal cramps, constipation, diarrhoea and stool irregularities. All symptoms decreased significantly over the 6 weeks treatment period (p < 0.0001), reflected simultaneously by a significant improvement of all items assessed via the QoL-SF-12. The SF-LDQ total score decreased under therapy from 6.3 ± 2.9 to 1.4 ± 2.0 regarding frequency of dyspeptic symptoms and from 3.6 ± 3.8 to 0.7 ± 1.7 regarding their interference with normal activities, whilst the digestive symptoms evaluated with the global questionnaire total score decreased from 17.9 ± 6.4 to 4.9 ± 5.9 for their frequency and from 9.6 ± 9.7 to 1.2 ± 2.9 for their interference with normal activities. Tolerability was rated as very good or good by 89% of physicians and 91% of patients. The evaluation of the related laboratory parameters showed a high degree of safety. Boldocynara®, the tested traditional herbal blend, demonstrated in this study clearly good clinical value in terms of efficacy, safety and tolerability in the treatment of functional digestive disorders.

Preclinical antitumor activity of oral silibinin-meglumine in combination with erlotinib or gefitinib in the treatment of erlotinib- and gefitinib-resistant EGFR-mutant NSCLC mouse xenografts.

e19003 Background: Silibinin (SLB), a bioactive flavonolignan isolated from the dried fruits of milk thistle (Silybum marianum), suppresses the resistance to erlotinib (ERL) caused by the EGFR T790M mutation in NSCLC xenograft models. Poor water solubility and low bioavailability might severely limit the efficacy of SLB. The ability of SLB to overcome ERL resistance attributed to mechanisms other than the second-site EGFR mutations remains completely unexplored. Methods: Using PC-9 cells harboring the ERL-sensitizing EGFR exon 19-mutation ΔE746-A750, we developed ERL-refractory derivatives (PC-9 ERL-R) that lacked EGFR T790M mutation. An oral formulation of milk thistle extract enriched (30%) with a water-soluble form of SLB complexed with the excipient amino-sugar meglumine (SLB-m) was explored for its ability to inhibit the growth of PC-9 ERL-R xenografts. Results: In the absence of second-site EGFR mutations or the alternative activation of MET or AXL, acquired cross-resistance to ERL and GEF correlated with enhanced epithelial-to-mesenchymal transition (EMT) features. Single-agent SLB-m significantly decreased the overall tumor volumes of PC-9 ERL-R xenografts, which exhibited enhanced engraftment and faster growth compared with the ERL-/GEF-sensitive PC-9 parental xenografts. Combination treatment with ERL + SLB-m or GEF + SLB-m significantly suppressed tumor growth (&gt; 90%) compared with single-agent treatment. The SLB-m treatment fully inhibited the development of an EMT phenotype in the ERL-/GEF-refractory cells in vitro. Systemic SLB-m treatment significantly affected the expression of EMT-related transcription factors in the ERL-/GEF-refractory xenografts. Conclusions: The oral administration of SLB-m delays tumor progression in ERL-/GEF-refractory EGFR-mutant NSCLC mouse xenografts. Given that the EMT phenomenon is required by a multiplicity of mechanisms of acquired resistance mechanisms to ERL, our data might facilitate the design of clinical trials to test the administration of SLB-m in combination with ERL or GEF in patients with EGFR-mutated tumors that progress to these drugs.

Silibinin's mode of action against hepatitis C virus

Background: Silymarin extracted from milk thistle fruit (Cardui fructus) has been used as a hepatoprotective drug since ancient times. A few years ago first data emerged suggesting antiviral activity against hepatitis C virus (HCV) for silibinin, a silymarin component. The mechanisms by which HCV suppression occurs have not been fully characterized yet. A substantial amount of data has been produced leading to different hypotheses how silibinin interacts with the HCV reproductive cycle.

Absolute Configuration of Isosilybin A by X-ray Crystallography of the Heavy Atom Analogue 7-(4-Bromobenzoyl)isosilybin A

Isosilybin A (1) is one of the major flavonolignans that constitute silymarin, an extract of the fruits (achenes) of milk thistle (Silybum marianum). The chemistry of the Silybum flavonolignans has been studied for over four decades, and the absolute configuration of 1 has been determined previously by electronic circular dichroism and X-ray crystallography via correlating the relative configuration of the phenylpropanoid moiety to the established absolute configuration of the 3-hydroxyflavanone portion of the molecule. Herein we report the X-ray crystallographic structure of the product of the reaction of 1 with 4-bromobenzoyl chloride, and, thus, the absolute configuration of 1 was established as (2R, 3R, 7″R, 8″R) directly via X-ray crystallography of an analogue that incorporated a heavy atom. The results were consistent with previously reported assignments and verified the absolute configuration of the diastereoisomer of 1, isosilybin B, and the related diastereoisomeric regioisomers, silybin A and silybin B.

Rumen degradability and whole tract digestibility of flavonolignans from milk thistle (Silybum marianum) fruit expeller in dairy cows

The objective of this study was to determine rumen degradability and total digestibility of flavonolignans from a milk thistle fruit expeller in dairy cows considering milk production and changes in plasma flavonolignans. The experiment was carried out on three lactating Holstein cows and was divided into three periods as follows: preliminary period (Pr, 3 days) was used for the diet stabilization followed by the adaptation period (A, 6 days) in which the treatment was applied and by the balance period (B, 4 days). Cows were fed individually twice a day (6:40 and 16:40 h) ad libitum the diet based on maize silage, lucerne hay and supplemental mixture. In the periods A and B the diet was supplemented with 150 g/day of milk thistle fruit expeller applied in two equal portions at each feeding. Average daily intake of dry matter and basic nutrients was similar in all periods (P &amp;gt; 0.05). Milk yield and composition were not affected by the treatment (P &amp;gt; 0.05). The milk thistle fruit expeller used in this experiment contained 4.10 &amp;plusmn; 0.10 mass percentage of the silymarin complex. Digestibility of silybin A and silybin B was 40.0 and 45.5%, respectively. Digestibility of other components of the silymarin complex was 100%. The highest value of the effective degradation was found for taxifolin (59.11%), while the effective degradation of the other flavonolignans ranged from 23.28 to 35.19%. Animals receiving the milk thistle fruit expeller had a higher content of plasma conjugated silybin (P &amp;lt; 0.001) than those without its supplementation.

Effect of sowing date and rate on the yield and flavonolignan content of the fruits of milk thistle (Silybum marianum L. Gaertn.) grown on light soil in a moderate climate

In the moderate climate of Poland it is recommended that milk thistle (Silybum marianum L. Gaertn.) be grown on fertile soils. The plant, however, develops a strong root system, so a working hypothesis has developed that cultivation can be extended to light soils with periodic water deficits. The aim of the present research was to determine the effects of sowing milk thistle on light soil at different dates and rates on the achene yield and flavonolignan content. This experiment was carried out during 2004–2006 at the Mochelek Experiment Station of the University of Technology and Life Sciences in Bydgoszcz (53°13′ N; 17°51′ E). The average fruit yields were 1.23tha−1; those of silymarin were 26.5kgha−1. The moisture and thermal conditions during the research years caused the fruit yields to range from 0.55 to 1.68tha−1 and silymarin yields from 13.3 to 35.4kgha−1. Delaying sowing from early to mid-April increased the plant density and decreased numbers of inflorescences and fruits per inflorescence; as a result, no effect of sowing date on fruit yield was found. Delaying the sowing date increased silymarin content by about 0.4% and its yield by 5.3kgha−1. Increasing the sowing rate from 12 to 24kgha−1 resulted in a slight (40kgha−1) but significant increase in achene yield; however, it did not affect the silymarin content. The average silymarin content in fruits was 2.18%. The ratio of silydianin to silychristin was 1:2.2, and the ratio of silydianin to the sum of silybinin and isosilybinin was 1:3.3.

Silibinin in the treatment of chronic hepatitis C – A review of the latest preclinical and clinical findings

Aims: Silymarin, the extract from milk thistle fruits (Silybum marianum) has been used as a hepatoprotectant since ancient times. The potential benefit of silymarin in the treatment of viral induced liver diseases continues to be discussed controversially. Silibinin, a major component of silymarin, is a well known potent scavenger of several oxidizing species. It has been shown in the past that oxidative stress might mediate HCV-induced activation of STAT-3 and at the same time to impair IFN-alpha signalling, causing resistance to the antiviral action of IFN-alpha in chronically HCV infected patients. Consequently, the hypothesis has been developed that antioxidative properties of silymarin or its constituent silibinin may theoretically improve the response in nonresponder hepatitis C patients to the standard of care (SOC) antiviral therapy with pegylated interferon and ribavirin (PegIFN/RBV). Clinical findings: An investigator intiated a multicenter, open-label clinical trial (Prof. Ferenci, University Hospital of Vienna) titled „Nonresponder Study: Multicenter Study to Evaluate the Efficacy of Silymarin in Addition to Combination Therapy with Pegylated Interferon Alfa 2A and Ribavirin in Patients with Chronic Hepatitis C“. The objective of the trial was initially to use silibinin as an antioxidant in hepatitis C patients not responding to SOC. Unexpectedly, silibinin administered parenterally, showed a powerful antiviral activity. A recently done interims analysis showed at week 25 that 57% of the patients (still under PegIFN and RBV combination therapy) were HCV RNA negative. Another therapeutic approach of intravenous administration of silibinin in patients non responding to SOC is the so called „rescue treatment“. After completing at least 24 weeks of SOC therapy non-responding patients received additionally 20mg/kg/d silibinin intravenously for 15 days. Thereafter PegIFN/RBV was continued. It could be shown that silibinin is effective on treatment of nonresponders to full dose of PegIFN/RBV combination therapy. A slightly different approach has been followed by Biermer & Berg in Germany who used silibinin for the successful treatment of a severe CHC-patient in the context of ribavirin. Pre-clinical findings: Meanwhile, the ability of silibinin to inhibit HCV enzymatic functions and replication has been tested in HCV RNA-dependent RNA polymerase (RdRp) and NS3/4A protease enzyme assays. Its ability to inhibit replication of an HCV genotype 1b replicon model and the JFH1 infectious HCV model in cell culture was also studied. It could be shown that silibinin inhibited RdRp function and also inhibited both HCV genotype 1b replicon replication and HCV genotype 2a strain JFH1 replication in cell culture. Summary: Intravenous silibinin has been shown to be a potent antiviral agent in patients with chronic HCV not responding to standard therapy with pegylated interferon plus ribavirin. Moreover, silibinin has been found to be a direct inhibitor of hepatitis C virus RNA-dependent RNA polymerase in vitro.

Production and quality of milk thistle (Silybum marianum[L.] Gaertn.) cultivated in cultural conditions of warm agri-climatic macroregion

A polyfactorial field experiment was established and investigated during vegetation periods from 2004 to 2007 at the Doln&amp;aacute; Malanta locality (Nitra district, Slovakia). The following parameters were measured: (1) yields of milk thistle (Silybum marianum [L.] Gaertn.) achenes, i.e. fruits, in 2004&amp;ndash;2007; (2) content of silymarin in dry fruits of milk thistle in 2006&amp;ndash;2007; and (3) total yields of silymarin per ha in 2006&amp;ndash;2007. Factors of the experiment were as follows: (1) crop residues of cultivated pre-crop (no crop residues &amp;ndash; K, with crop residues &amp;ndash; R); (2) cultivation of freezing-out intercrop (no intercrop &amp;ndash; B, with intercrop &amp;ndash; M); (3) fertilization using artificial fertilizers (no fertilization &amp;ndash; O, with fertilization &amp;ndash; F); (4) year of cultivation (2004&amp;ndash;2007). The highest yields of milk thistle fruits were recorded in 2006: from 1,426.5 kg/ha (RBO variant &amp;ndash; incorporated crop residues without intercrop, no artificial fertilizers) to 1,832.0 kg/ha (KBF variant &amp;ndash; without crop residues, without intercrop and with application of artificial fertilizers). The highest content of silymarin complex in dry fruits of milk thistle was measured in 2007: from 15.14 mg/kg (RMF &amp;ndash; with crop residues, intercrop and fertilization) to 20.01 mg/kg (KBO &amp;ndash; without crop residues, intercrop and fertilization). The highest total yield of silymarin per ha was recorded in investigated variants in 2006; in variant without crop residues it ranged from 16.45 kg/ha (KMF &amp;ndash; with intercrop, with fertilizers) to 24.62 kg/ha (KMO &amp;ndash; with intercrop, no fertilization).

Interaction of milk-thistle-fruit flavanonols with Langmuir monolayers of lecithin and bilayers of liposomes

Interactions of silybin and dihydroquercetin (taxifolin), flavanonols from milk thistle [Silybum marianum (L.) Gaertn.] fruits, with Langmuir monolayers of lecithin and bilayers of liposomes are compared. It is established that the investigated flavanonols have different mechanisms of action. Taxifolin produces predominantly membrane-stabilizing action whereas silybin is characterized by immobilization in the hydrophobic part of the phospholipid bilayer with the formation of more hydrophilic micellar structures. The presence of silybin and taxifolin in the liquid extract of milk thistle fruits suggests that a dual mechanism of action may occur in this preparation and also in other combined medicines based on these fruits. The results of this study show good prospects for creating combined preparations based on milk thistle fruit, taxifolin, and other flavonoids (quercetin, rutin, diosmin, etc.) possessing pronounced membrane-stabilizing action.

Variation in Flavonolignan Concentration of Milk Thistle (Silybum marianum) Fruits Grown in Iran

ABSTRACT This study was conducted to analyze the genetic variation of silymarin and the corresponding flavonolignans in the fruit (achenes) of 32 ecotypes of milk thistle, Silybum marianum (L.) Gaertner, collected from the north, northwest, south, and southwest of Iran and two improved commercial varieties, one from England (CN Seeds, Ltd., Ely, United Kingdom) and one from Hungary (Budakalaszi, Budakalasz). A higher level of genotypic variation, heritability, and genetic gain was observed for silybin A and B in the studied ecotypes as compared with the two accessions, indicating that these traits could be further improved. In contrast, silymarin content and yield showed only moderate receptiveness for improvement. For silychristin and silydianin, high variation was obtained only in ecotypes originating from the south and southwest regions of Iran. Factor analysis resulted in two factors, accounting for about 91 percent of the total variation of the investigated characters. On this basis, three groups each with distinct chemotypic properties could be identified. Discriminant analysis verified the results of factor analysis and separated the groups.

Hepatobiliary Excretion of Silibinin in Normal and Liver Cirrhotic Rats

Silibinin is the main biologically active flavonolignan extracted from the seeds and fruits of milk thistle and has potential efficacy in the treatment of liver disease. The aim of the present study was to examine the hepatobiliary excretion of silibinin and its effect on dimethylnitrosamine (DMN)-induced liver cirrhosis. The experiments were divided into five groups: 10, 30, and 50 mg/kg silibinin alone, 30 mg/kg silibinin coadministered with cyclosporin A (CsA), and 50 mg/kg silibinin with liver cirrhosis induced by DMN. The data indicated that silibinin had dose-related pharmacokinetics in the dose ranges of 10 to 50 mg/kg. All of the unconjugated or total (unconjugated + conjugated) silibinin concentrations in the bile were significantly higher than those in plasma at the sampling time points at each dose, suggesting active hepatobiliary excretion. When coadministered with CsA, the area under the concentration versus time curve (AUC) in bile was significantly decreased. This result suggested that the active silibinin efflux might be partially inhibited by P-glycoprotein. In the DMN-induced liver cirrhotic rats, the AUC of plasma unconjugated silibinin was reduced by 53%; however, total silibinin was increased by 182%. These results together suggest that the phase II conjugative reaction of silibinin was blocked by treatment with DNM.

Silyamandin, a New Flavonolignan Isolated from Milk Thistle Tinctures

Our investigations into the stability of tincture preparations of milk thistle fruit [ Silybum marianum L. Gaertn. (Asteraceae)] have led to the characterization of a new flavonolignan 4-(4-hydroxy-3-methoxyphenyl)-7-[(2 R,3 R)-3,5,7-trihydroxy-4-oxochroman-2-yl]-1-oxo-1,3,3a,4,5,7a-hexahydro-2-benzofuran-5-carboxylic acid called silyamandin (1). Incubation of the tincture at 40 degrees C for 3 months resulted in an increase in the level of this compound, as observed in the LC/DAD silymarin profile.

Pressurized water versus ethanol as a Silybum marianum extraction solvent for inhibition of low-density lipoprotein oxidation mediated by copper and J774 macrophage cellsThis article is one of a selection of papers published in this special issue (part 1 of 2) on the Safety and Efficacy of Natural Health Products.

Silybum marianum contains flavonolignans, termed silymarin (SM), that are therapeutic agents for many inflammation-based diseases including atherosclerosis. Oxidation of human low-density lipoprotein was induced by CuSO4 or J774 macrophage cells and measured by the formation of thiobarbituric acid reactive substances (TBARS). SM was extracted by pressurized hot water (PHWE) or ethanol, and the effects of these extracts on TBARS formation were evaluated in comparison with those of SM preparations made from blending masses of individual flavonolignan standards in ratios identical to those of the water and ethanol extracts. Ethanol-extracted SM and its blended counterpart inhibited the generation of TBARS by 82% and 43%, respectively, at 150 mumol/L doses. TBARS levels in the presence of 150 micromol/L of the PHWE and its blended SM counterpart were reduced by 84% and 38%, respectively. Extracts from milk thistle fruit displayed higher protective effects than blended SM solutions of the same concentration with an identical compositional makeup. The appearance of degradation peaks in the water extract did not create any cytotoxic effects. Results of this study confirm that PHWE can be used to extract flavonolignans from milk thistle and that these extracts may possess therapeutic potential different from or beyond that of traditional organic solvent preparations.

Mechanisms involved in the gastro-protective effect of STW 5 (Iberogast®) and its components against ulcers and rebound acidity

The protective effect of a commercial preparation (STW 5, Iberogast), containing the extracts of bitter candy tuft, lemon balm leaf, chamomile flower, caraway fruit, peppermint leaf, liquorice root, Angelica root, milk thistle fruit and greater celandine herb, against the development of gastric ulcers was previously reported in an earlier publication (Khayyal et al., 2001). All extracts produced a dose dependent anti-ulcerogenic effect associated with a reduced acid output, an increased mucin secretion, an increase in prostaglandin E(2) release and a decrease in leukotrienes. The effect on pepsin content was not uniform and did not seem to bear a relationship with the anti-ulcerogenic activity. The best effects were observed with the combined formulation, STW 5. Furthermore, the effect of the latter in protecting against the development of rebound gastric acidity was examined experimentally in rats and compared with the effect of some commercial antacid preparations (Rennie, Talcid and Maaloxan). A model of testing rebound acidity was developed by inducing a marginal increase in gastric acidity through the administration of indomethacin, in such a way that it could be easily neutralized, allowing any eventual secondary increase in acidity to be measured within a few hours of administration. In addition, the serum gastrin level was measured after drug treatment to establish any correlation between it and any rebound acidity. The results obtained demonstrated that STW 5 did not only lower the gastric acidity as effectively as the commercial antacid, but it was more effective in inhibiting the secondary hyperacidity. Moreover, STW 5 was capable of inhibiting the serum gastrin level in rats, an effect which ran parallel to its lowering effect on gastric acid production.

Pharmaceutical prerequisites for a multi-target therapy

The quality of a phytomedicine is defined by the quality of the herbal drug, the manufacturing of the drug preparations and the properties of the finished product, taking into account the special requirements of the individual herbal species in accordance with Good Manufacturing Practice (GMP) standards [2003. Medicinal Products for Human and Veterinary Use. Eudralex, vol. 4 (2003/94/EC)]. The quality control of the complete process is based on pharmacognostic methods, characteristic fingerprint chromatograms, defined amounts of marker substances, physicochemical characteristics and microbiological monitoring. For a herbal multi-component preparation used in multi-target therapy, these pharmaceutical prerequisites have to be ensured for all components and for their combination, as is exemplified by Iberogast((R)) (STW 5) a fixed combination of hydroethanolic extracts of bitter candytuft (Iberis amara), angelica root (Angelicae radix), milk thistle fruit (Silybi mariani fructus), celandine herb (Chelidonii herba), caraway fruit (Carvi fructus), liquorice root (Liquiritiae radix), peppermint herb (Menthae piperitae folium), balm leaf (Melissae folium) and chamomile flower (Matricariae flos) using in the therapy of gastrointestinal complaints (Rösch et al., 2006). The prerequisites for the quality of each of its components according to actual standards are at first the cultivation of the plant material according to the Guidelines for Good Agricultural Practice (GAP) conditions of Medicinal and Aromatic Plants [1998. Z. Arzn. Gew. Pfl. 3, 166-178] to yield a defined raw material of high quality. Characteristic compounds of the extracts had to be identified and different analytical methods such as HPLC, with low coefficients of variation had to be developed to analyze each of the standardized ethanolic extracts and the finished product. At the example of the extract of I. amara these necessary investigations are described. The variability of the plant material in its natural habitats, the identification of characteristic compounds and exemplary chromatograms for fingerprint evaluation and quantification are shown. These data are required for characterization of the profile of the active substances in the finished product.